This invention pertains to the art of collapsible containers and more particularly to automatically-operating bottom structures for use with collapsible containers. The invention is specifically applicable to eight-sided collapsible containers of the type used in the meat packing industry and will be described with particular reference thereto. In an alternative embodiment, the invention combines an automatically-operating bottom structure with a collapsible container having a plastic liner affixed to the interior panel surfaces thereof. As the bottom structure is automatically-operated, the plastic liner is drawn into the container as it opens. It will be appreciated, though, that the invention has broader applications such as for use with multi-sided collapsible containers for products in other industries or for merchandising, store displays or the like.
One prior art automatically-operated bottom structure is disclosed in U.S. Pat. No. 4,856,705 to Carr, et al. That patent describes a box which may be unfolded in a simple manner from a closed to a fully-expanded condition by an operator inserting his hands into the top portion and extending the folded blanks apart to form the fully-expanded condition. As that occurs, a band flap spans a traverse distance between opposing panels. Bottom flap panels are then manually folded downwardly and interdigitally fitted with one another. The band flap prevents the bottom flap panels from pivoting more than 90.degree. relative to their respective vertical side panels.
One problem with the above discussed automatically-operated box and many others like it is that an operator must bend over and insert his hands into the box to push apart the pair of vertical side panels. In addition, once the box is opened, the operator must then reach down into the box to interdigitally connect the bottom flap panels with one another. This procedure is inherently awkward, especially for large boxes, labor intensive, and time consuming.
In certain applications, it is desirable that a box be opened by an operator by merely applying pressure to the outside surfaces of a pair of opposing panels forming the box. One such application is the meat packing industry where reaching into a fresh box to operate it into a fully-expanded condition may cause contamination thereof.
The present invention contemplates a new and improved automatically-operating bottom structure for use with a collapsible container adapted to be selectively moved between a folded-flat condition and a fully-expanded condition merely through application of opposing forces to outside surfaces of the container panels.
The automatically-operating bottom structure of the invention comprises a band pivotally connected to each of a first pair of panels forming a collapsible container. The band includes two sections pivotally connected to one another about an intermediate pivotal axis substantially parallel to the pivotal axes between said band and the first pair of panels. The two sections are arranged with respect to one another at an included angle of about 0.degree. when the container is in a folded-flat condition and arranged with respect to one another at an included angle of about 180.degree. when the container is in a fully-expanded condition. A first bottom flap is connected to a first one of the plurality of collapsible container side panels. The first bottom flap engages a first surface of the band and forms an included angle of about 90.degree. with respect to the first panel when the container is in the fully-expanded condition. A second bottom flap is connected to a second one of the plurality of panels and engages a second surface opposite the first surface of said band and forms an included angle of about 90.degree. with respect to the second panel when the container is in the fully-expanded condition. Lastly, a web panel connects the first bottom flap with the second bottom flap. The web panel moves in response to movement of the first bottom flap. Similarly, the second bottom flap moves in response to motion in the web panel. Thereby, motion of the first flap causes motion in the second flap.
Accordingly, it is a general object of the present invention to provide an improved automatically-operating bottom structure for use with an octagonal collapsible container.
Another object of the present invention is to provide a plastic or thin paper lining in an octagonal container, the liner which automatically unfurls with the automatic operation of the bottom structure.
These and other objects and advantages of the present invention will become apparent to those skilled in the art upon a reading and understanding of the following detailed description.